| Abstract
| - Many uncatalyzed bromate oscillators (UBO's) undergo oscillationsin electrochemical potentialwithout any observable color change in a closed, stirred (batch)system. We have investigated the effects ofadding a wide variety of redox indicators, including diphenylaminederivatives, azo dyestuffs, triphenylmethanederivatives, diimine chelate complexes, and methylene blue to UBO's.We find that in many cases the indicatorsmake the batch oscillations strikingly visible and also allowobservation of spatial pattern formation (concentricrings and spirals) in a thin, unstirred layer of solution. In somesystems, the indicators act merely to makevisible changes in redox potential, while in others they play an activerole in the chemistry, and added indicatorcan lengthen the duration of oscillations or regenerate oscillations orpatterns once this behavior has ceased.
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